Line data    Source code

       1             : /* +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
       2             :    Copyright (c) 2013-2020 The plumed team
       3             :    (see the PEOPLE file at the root of the distribution for a list of names)
       4             : 
       5             :    See http://www.plumed.org for more information.
       6             : 
       7             :    This file is part of plumed, version 2.
       8             : 
       9             :    plumed is free software: you can redistribute it and/or modify
      10             :    it under the terms of the GNU Lesser General Public License as published by
      11             :    the Free Software Foundation, either version 3 of the License, or
      12             :    (at your option) any later version.
      13             : 
      14             :    plumed is distributed in the hope that it will be useful,
      15             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      16             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      17             :    GNU Lesser General Public License for more details.
      18             : 
      19             :    You should have received a copy of the GNU Lesser General Public License
      20             :    along with plumed.  If not, see <http://www.gnu.org/licenses/>.
      21             : +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ */
      22             : #include "Colvar.h"
      23             : #include "ActionRegister.h"
      24             : #include "core/PlumedMain.h"
      25             : #include "core/Atoms.h"
      26             : 
      27             : #include <string>
      28             : #include <cmath>
      29             : 
      30             : namespace PLMD {
      31             : namespace colvar {
      32             : 
      33             : //+PLUMEDOC COLVAR CONSTANT
      34             : /*
      35             : Return one or more constant quantities with or without derivatives.
      36             : 
      37             : Useful in combination with functions that
      38             : takes in input constants or parameters.
      39             : 
      40             : \par Examples
      41             : 
      42             : The following input instructs plumed to compute the distance
      43             : between atoms 1 and 2. If this distance is between 1.0 and 2.0, it is
      44             : printed. If it is lower than 1.0 (larger than 2.0), 1.0 (2.0) is printed
      45             : 
      46             : \plumedfile
      47             : cn: CONSTANT VALUES=1.0,2.0
      48             : dis: DISTANCE ATOMS=1,2
      49             : sss: SORT ARG=cn.v_0,dis,cn.v_1
      50             : PRINT ARG=sss.2
      51             : \endplumedfile
      52             : 
      53             : In case you want to pass a single value you can use VALUE:
      54             : \plumedfile
      55             : cn: CONSTANT VALUE=1.0
      56             : dis: DISTANCE ATOMS=1,2
      57             : sss: SORT ARG=cn,dis
      58             : PRINT ARG=sss.1
      59             : \endplumedfile
      60             : 
      61             : */
      62             : //+ENDPLUMEDOC
      63             : 
      64             : using namespace std;
      65             : 
      66         102 : class Constant : public Colvar {
      67             :   vector<double> values;
      68             : public:
      69             :   explicit Constant(const ActionOptions&);
      70             :   virtual void calculate();
      71             :   static void registerKeywords( Keywords& keys );
      72             : };
      73             : 
      74        7424 : PLUMED_REGISTER_ACTION(Constant,"CONSTANT")
      75             : 
      76          34 : Constant::Constant(const ActionOptions&ao):
      77          34 :   PLUMED_COLVAR_INIT(ao)
      78             : {
      79          34 :   bool noderiv=false;
      80          68 :   parseFlag("NODERIV",noderiv);
      81          68 :   parseVector("VALUES",values);
      82             :   vector<double> value;
      83          68 :   parseVector("VALUE",value);
      84          40 :   if(values.size()==0&&value.size()==0) error("One should use either VALUE or VALUES");
      85          62 :   if(values.size()!=0&&value.size()!=0) error("One should use either VALUE or VALUES");
      86          34 :   if(value.size()>1) error("VALUE cannot take more than one number");
      87          34 :   if(values.size()==0) {
      88           6 :     values.resize(1);
      89           6 :     values[0]=value[0];
      90             :   }
      91          34 :   checkRead();
      92          34 :   if(values.size()==1) {
      93          33 :     if(!noderiv) addValueWithDerivatives();
      94           0 :     else addValue();
      95          33 :     setNotPeriodic();
      96          33 :     setValue(values[0]);
      97           1 :   } else if(values.size()>1) {
      98           8 :     for(unsigned i=0; i<values.size(); i++) {
      99           2 :       std::string num; Tools::convert(i,num);
     100           4 :       if(!noderiv) addComponentWithDerivatives("v_"+num);
     101           0 :       else addComponent("v_"+num);
     102           4 :       componentIsNotPeriodic("v_"+num);
     103           4 :       Value* comp=getPntrToComponent("v_"+num);
     104           2 :       comp->set(values[i]);
     105             :     }
     106             :   }
     107             : // fake request to avoid errors:
     108             :   std::vector<AtomNumber> atoms;
     109          34 :   requestAtoms(atoms);
     110          34 : }
     111             : 
     112          35 : void Constant::registerKeywords( Keywords& keys ) {
     113          35 :   Colvar::registerKeywords( keys );
     114          35 :   componentsAreNotOptional(keys);
     115          35 :   useCustomisableComponents(keys);
     116          70 :   keys.remove("NUMERICAL_DERIVATIVES");
     117         140 :   keys.add("optional","VALUES","The values of the constants");
     118         140 :   keys.add("optional","VALUE","The value of the constant");
     119         105 :   keys.addFlag("NODERIV",false,"Set to TRUE if you want values without derivatives.");
     120         140 :   keys.addOutputComponent("v","default","the # value");
     121          35 : }
     122             : 
     123             : // calculator
     124        2847 : void Constant::calculate() {
     125        2847 :   if(values.size()==1) {
     126        2842 :     setValue(values[0]);
     127        2842 :     return;
     128             :   }
     129          40 :   for(unsigned i=0; i<values.size(); i++) {
     130          10 :     Value* comp=getPntrToComponent(i);
     131          10 :     comp->set(values[i]);
     132             :   }
     133             : }
     134             : 
     135             : }
     136        5517 : }
     137             : 
     138             : 
     139             :